The buildup to the "Doctor Who" 50th anniversary episode "The Day of the Doctor" on Nov. 23 continued on Thursday with a special surprise for longtime fans of the Doctor. The BBC posted a new six-minute minisode titled "The Night of the Doctor" that fills in a vital bit of the Doctor's history.

Back in 1996, Paul McGann played the Doctor in a one-shot TV movie that attempted to revive the "Doctor Who" franchise after a seven-year absence from TV screens. The film turned out to be McGann's only spin in the role before the series was revived more successfully in 2005.

While all the Doctors before and after McGann were shown transitioning in and out of the role through the Doctor's famous regenerations, the gap between McGann as the eighth Doctor and Christopher Eccleston as the ninth has always been completely unexplored.

Not to spoil anything about this very short adventure, written by current "Doctor Who" show runner Steven Moffat, but a major lingering question for fans both old and new will be answered and anticipation for the 50th anniversary special is higher than ever. Why? Because McGann's unexpected appearance in this special means many more surprises could be in the offing.

Currently, three versions of the Doctor -- David Tennant, Matt Smith and John Hurt -- are set to appear in the film, along with companions Jenna Coleman and Billie Piper.

But who else could be spotted? The world will find out at the same time.

Back in 1962, television writer Anthony Coburn penned the script for the first episode of the BBC science fiction series "Doctor Who" and included the first appearance of the mysterious Doctor's spacecraft-time machine that resembled a blue police call box and was called a TARDIS. Now, 50 years...

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